Classification and standards of experimental animal / 实验动物分级及其标准

There are four levels for experimental animal in accordance with microbiological control standards:


Level I: Common animals (CV) are general animals that are not subject to special control. They are required not to have the pathogen and for main infectious diseases for human and animal diseases and pathogen for fulminating infectious disease. In order to prevent infectious diseases, it is necessary to take certain measures to ensure reproducibility of the results of the experiment during animal breeding (The experiments carried out by different operators and in different time in accordance with experimental procedures on same type of animals should have similar results). 


Level II: Clean animals (CL) are required not to have the pathogen for main infectious diseases for human and animal diseases.


Level III: Animals without special pathogen (SPF) are required to reach level II and exclude some designated pathogen. High efficiency air filter sterilization, UV sterilization, three glycol vapor spray and aqueous solution of lithium chloride spray can be used for sterilization.


Level IV: sterile animal (GF) or gnotobiotic animal (GN). Sterile animals are required not to have any microorganisms that can be detected by existing method. Gnotobiotic animals are required not have implanted with one or several kinds of known microorganisms in the sterile animal. 


Sterile animals and animals with known bacteria or without special pathogen need to be kept in sterile environment, this kind of environment is at present known as barrier environment in the world, that is, using a barrier to separate animals from surrounding pollution.


A .Isolation system / 隔离系统  

It is a system for breeding animals in a container with gloves and it is used to keep sterile animals and terrestrial animals. The cleanliness inside must be level 100 according to the requirements of microorganism, but rooms and operators shall not be considered as for sterile room.


B.Shield system / 屏障系统   

The sterile room with level 10,000-100,000 can be used as feeding room, which is mainly used for long-term breeding of animals without special pathogen. Strict management should be carried out when entering the room such as shower, change clothes, etc.


C.Semi-shield system / 半屏障系统

Broaden management of people and objects coming in and out of the room. The composition of the plane is roughly the same as the shield system.


D.Laminar frame system / 层流架系统   

Cages should be placed in a clean horizontal laminar air. It is commonly used in small scale breeding, but there is a risk of contamination in an ordinary room for feeding, operation and handling. Semi-shield can be supplemented.


E.Open System / 开放系统   

It is the system for people, objects and air coming in and out of the room without eliminating pollution, but usually a certain degree of cleaning management should be carried out.


Basic requirements for animal room design / 动物房设计的基本要求

(1) Site: quiet and hygienic.              (2) Layout: preparation area, feeding area and experimental area. People flow, goods flow and animal flow are separated (one-way); purification, sterilization, pest control are required.              (3) Building: have a clean corridor, feeding room, pollution corridor and other rooms.              (4) Air conditioning system: temperature, humidity and air velocity are controllable with certain amount of ventilation volume and air pressure.             (5) Lighting: use fluorescent lamps for animal room without windows and use glass windows for animal room with windows to filter UV. 12h lighting and 12h dark are required.              (6) Water supply: drinking water and purified water.

(1) 选址:僻静、卫生。          (2) 布置:分为准备区、饲养区、实验区。要求人流、物流、动物流分开(单向流程); 要求净化、灭菌、防虫。          (3) 建筑:要求有洁净走廊,饲养室,污染走廊以及其他各室。          (4) 空调系统:有可控制的温度和湿度、气流速度和分布,有一定的换气量和气压。          (5) 照明:无窗动物房使用荧光灯,有窗动物房可安装玻璃窗,以滤去紫外线。要求12h亮,12h暗。          (6) 供水:有饮用水和精制水。

Configuration of animal room / 动物房的设置

Animal room, activity area and corresponding auxiliary room should be built according to different species and different levels of experimental animals. The site should be quiet and clean without adverse external influence.


Animal room must be full of light with good ventilation, have clean ground and no water accumulation; ceiling and walls must be easy to clean and disinfect; exterior walls, roof, ceiling, doors and windows and pipelines must be free from animals, mosquitoes and other pests. Indoor temperature should be controlled at in 18-29℃, relative humidity 40%-70%, noise 60dB.


The animal density in cages cannot be too large. Air supply device, exhaust device, cooling and heating equipment should be equipped. Dedicated sewage and drainage facilities must be built to prevent spread of pathogens. All cages should be cleaned and disinfected regularly. Pad material must be disinfected by high temperature/pressure or drugs and replaced in time. Indoor ammonia concentrations must be below 15 mg/m3.

笼内动物密度不能太大,要有送风、排风、降温及保暖设备。须有专用的排污、排水设施,防止病原扩散。各种笼具要定期清洗消毒,垫料须经高温高压或药物消毒并及时更换,使室内氨浓度在15 mg/m3以下。